The present invention relates to an analog style electronic watch which indicates time continuously, as opposed to digitally and incrementally. The watch includes an inner integrated circuit for generating pulses for electromagnetically driving indicator wheels and does not use a step motor and gears as do conventional analog style watches.
As illustrated in FIG. 6, a prior art analog style electronic watch circuit includes a static voltage generating regulator 12 and divider 14 for dividing pulses from a clock 11 which generates pulses, input-output circuit 17 for testing the count status of divider 14, reset input circuit 13 for resetting pulse periods, a pulse width controller 15 for controlling width of the pulses, and a pulse period generator 16 for driving a motor. The integrated watch circuit also includes motor output terminal 18 for driving a step motor 19 which converts electric energy to mechanical energy.
Prior art analog style electronic watches of this construction divide pulses from clock 11 by the divider(14). When the divided frequency is applied to the pulse width generator 15 through input-output logic 17, the pulse width generator 15 generates motor driving pulses of a pulse width to drive the second hand. The step motor driving pulses are applied to the pulse period generator 16 which determines their period in order that the second hand properly indicates 60 seconds.
An example of an analog style electronic watch of this construction is shown in Japan Utility Model Specification SHO 57-9752.
The prior art watch of this type drives one wheel with a step motor and uses a gear in order to drive the minute and hour hands rings. Several problems occur with this construction.
That is, in the prior art analog watch, if the step motor drives the second hand wheel, and the second hand wheel drives other wheels (e.g., a center wheel, minute wheel, and hour wheel), there is the problem with precision. Also, life of watch becomes less due to abrasion of the contact parts.
Moreover, as shown in Japan Utility Model Specification SHO 57-9752, prior analog style electronic watches consume more power. The electric power of a step motor consumes about two-thirds of the total energy requirement.